Dynamo-electric machine.



No. 633,64I. Patented Sept. 26, |899.

C. A. ECK.

DYNAIO ELECTRIC MACHINE.

(Application led July 2B, 1899.)

(No Model.)

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W rn/daaro@ 1 UNITED STATES PATENT OFFICE.

CHARLES A. ECK, OF NEVARK, NE\V JERSEY.

DYNAMO-ELECTRlC MACHINE.

SPECIFICATION forming part of Letters Patent No. 633,641, dated September 26, 1899.

Application filed July 28, 1899. Serial N0.'?25,355, (No model.)

To all whom t may concer/e:

Be it known that I, CHARLES A. ECK, a subject of the King of Sweden and Norway, residing at Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Dynamo- Electric Machines, of which the following is a specification.

My invention relates generally to improvements in dynamo-electric machines and particularly to the adaptation of the brush-holders and adjacent parts of same tothe construction of the frame or yoke shown and described in Patent No. 627,438, granted to me June 27, 1899.

To this end the invention consists in the improved brush-holders, the coniigurative adaptation of the brushes to same, and, broadly speaking, in the combination of cooperative elements contiguous to said brush-holders, as will be fully set forth farther on in the specification.

Several objections may be urged against the type of brush-holders now commonly usedsuch as, for instance, the comparative inaccessibility of the brushes when they are worn and it is desired to replace them, the inability to inspect the working parts of the brushholders without a laborious dismantling of part of the machine, and other awkward features of a like nature, all tending to reduce the efficiency of the motor. It has accordingly been the object of my invention to obvi- -ate these and similar disadvantages-in short, to provide a brush-holder so constructed and so arranged with regard to the surrounding parts of the machine as to be efficient in operation, cheap in construction, and easy of -access in all respects. Although changes may be made without departing from the spirit of myinvention, I believe these objects to be best attained by the construction shown in the accompanying drawings, in which- Figure 1 is a rear viewof my improved dynamo-electric machine, showing the brushholders with their brushes in position, the means used for securing said brush-holders to the motor, and the method of securing them "(the brush-holders) rigidly together. Fig. 2 is 4a detail view of one of the brushholders, showing also insulating disk and :screw-insulator. Fig. 3 is a second view of one of the brush-holders, looking at it from abo ve and at right angles to the position shown in Fig. Q, the brush being removed. Fig. et is a sectional view of one of the brush-holders, taken on line e a: of Fig. Fig. 5 is a detail view of a combined insulating brush-holder bracket and armature-shield. Fig. 6 is adetail view of an insulating-disk. Fig. 7 is au end view of one of the brushes, showing its cross-sectional outline.

Similar letters and numerals of reference indicate corresponding parts in the different views.

I shall describe a dynamo-electric machine embodying my invention and afterward pointout the novel features in the claims.

l indicates a yoke or frame. 2 is a central hole in the wall of same, serving both as a shaft-hole for the shaft of the armature and coinmutator and also, owing to its peculiarlyelongated form, as a means of introducing 'the field-coils into the yoke.

3 is the armature-shaft, supported in the bearing 4 by suitable means, a similar bearing being located on the opposite side of the frame to support the other end of the armature-shaft. These bearings may be of any desired construction suitable for the purpose, buteach bearingconsists,preferably,of ajournal 4",havingfourradially-disposed L..shaped arms arranged with regard to each other in an upper and a lower pair Ib and 4, respectively, each of which two pairs of arms terminates in a fastening-plate ed, which is screwed onto the frame. Lubricating means, such as an oil-cup 5, is furnished for lubricating the bearing.

G is the comm utator, and 7 is a combined insulating brush-holder bracket and armatureshield.Y This bracket or shield is formed in the shape of a Yfiat ring with two horizontallyextended arms and is provided with sixholes, as shown-three on each side of the central hole-the function of which will become apparent later on.

S are two interchangeable brush-holders, each having a fastening-piece 12 extending at an angle from the main body, with holes for the admission of screw-insulators 13. By means of these fastening-pieces and screws. the brush-holders are fastened to the frame. An insulating-disk 27 is interposed between IOO the fastening-pieces of the brush-holders and thc frame, and this, togothcl.' with the screwinsulators, 'forms a perfectinsulation. Each of these brush-holders is further provided with two projections S, having screw-cut holes, by means of the correspondi-ng screws of which the brush-holders are fastened on the combined insulating brush-holder bracket and armature-shield, thus securing a rigid connection between said brush-holders. rlhc portion 21, forming the bridge between the brush-holder and the fastening-piece of same, is furnished with a transverse hole 22 for the admission ofthe leading-out wires. (Not shown.) A second hole 2S is drilled at right angles to the iirst hole and is for the admission of a tightening-screw 24 to hold the wires in position. The wires are passed from the inside of the frame through theholew, located at each end of the bracket or shield 7, and

are then secured in the hole in cach of the brush-holders, as before mentioned. It will thus be seen that this bracket or shield 7 serves, first, as an insulating-bracket for holding the brush-holders, and, secondly, as a shield for preventing to a degree the admission of dust and impurities inside the frame of the motor, and consequently to the armature of same.

9 is the brush. The brush-holder is composed of an upper compartment 10 for holding the brush and a lower compartment l1, in which a spring-actuated plunger 12c works. The lower compartment 11 consists of a sleeve closed at one end and open at the other. Of this sleeve the portion 1i, which serves as a wall between the upper and lower compart` ments, has a longitudinal slot 1S, which extends a short distance beyond the point at which the upper compartment ends. A cutout 1811, located at right angles to the slot 1S and communicating with same, is provided in the sleeve at the point where the slot 1S terminates. The upper compartment 10 is simply formed of two walls 1G, rising from the upper surface of the sleeve 11. These walls are provided with ledges 17 at their upper edges, and one of the walls is further provided with a slot 10, permitting the admission of a collector-spring 19, retained between the wall and the projection 20, as shown. The lower compartment or sleeve 1l contains at its closed end the spring 25, which is coniined there by the plunger 19C. This plunger is in the form of a small cylindricalpiece 12 ofthe same diameter as the sleeve, or very nearly so, and has a pin 12b inserted, whose axis is at right angles to the axis of the piece 1211.

lVhen for some reason or other a brush is removed from its brush-holder after having been somewhat worn, it oftentimes happens that when it is inserted again it is turned upside down and worn the other way. In such cases a sharp point or apex will be formed on the brush which will cut into the mica strips of the commutator and tend to destroy the same. 'lo cbviate this, my brush is formed with a cross-sectional outline as shown in Fig. 7, where it will be noticed one side is shown as being slightly curved or raised in the middle, the purpose of this being` al'- ways to present the brush in the same way to the commutator, as it is impossible to insert the former into the brush-holder when turned upside down on account of the two ledges 17, formed at the top of the walls oi. the upper compartment 10. lVhen it is desired to insert a brush into the brush-holder, the plunger is carried back by means of the linger and given a turn, so as to make the pin rest in the cut-out 1S,where it is retained, as shown in Fig. The brush is now insei-ted from the rear, pushing the collectorspring aside as it travels along. 'lhe plunger is then turned so as to bring the pin out of the cut-out 18il and into line with the slot 18, thereby releasing it from its locked position, and the plunger actuated by the spring will be pushed forward until it encounters the brush, which latter it will bring to bear against the comm utator with a const-ant pressure. Then it is desired to remove the brush, the plunger is simply brought back and turned into its locked position, when the brush can be slid out without any difficulty.

As the armature-shaft rotates at a high rate of speed, it has a tendency toimpart a vibrating movement t-o the brushes, causing the latter to rattle in a disagreeable way. This diflicultyI have overcome by the aid of the collector-spring, which takes up this vibrating motion and prevents the rattling noise. It will be noticed that owing to the direction of the motion of the armature-shaft, which is in the direction of the arrow-head, the collector-spring is located at the lower side and upper side of the brush-holders, respectively, on the right and left hand side of the machine, looking at it from the back.

It sometimes occurs that a layer of dust is formed between the brush-holder and the brush, causing thereby the circuit to be impaired. This is also obviated by the collectorspring, inasmuch as owing to the constant friction occasioned by the taking up of the motion of the brush by the collector-spring there will always be a clean surface free from dust and the circuit will remain unimpaircd.

lt will thus be seen that my improvements combine simplicity of construction with a very high efiicien'cy and that they tend in all ways to increase the facilityl with which the brush-holders and surrounding parts can be inspected and repaired when occasion rcquires it 5 also, that they decrease to a very great extent the disagreeable features occasioned by the clumsy mechanical constructions hitherto employed in this art.

Having thus described my invention, what I claim is- 1.. A brush-holder having two superposcd IOO IIO

compartments extending parallel to each other and a fastening-piece extending at an angle to the said compartments, substantially as described.

2. Ina brush-holder having two superposed compartments extending parallel to each other, the combination with the portion forming the wall between said compartments of a slot, and a cut-out extending at right angles to the axis of said slot, substantially as described.

3. In abrush-holder having two superposed compartments extending parallel to each other and of the character set forth, the combination with the lower compartment of a spring-actuated plunger, substantially as described.

4. In a brush-holder of the character set forth, a lower compartment consisting of a sleeve closed at one end, an upper compartment consisting of two walls 'formed on the upper side of the lower compartment, each wall having a ledge on its upper edge, said upper compartment having both ends open, and a collector-spring inserted in one of the walls, a longitudinal slot formed in the wall separating the two compartments, a cut-out communicating with such slot and a springactuated plunger of the character set forth substantially as described.

5. The combination in a brush-holder of the character set forth of an upper compartment for holding a brush, a lower compartment, a spring-actuated plunger operating in the lower compartment, and upon the brush in the upper compartment, a fastening-piece extending at an angle to the two compartments, means formed between the lower compartment and the fastening-piece for holding the leading-out wires, substantially as described.

6. In a brush-holder having two superposed compartments extending parallel to each other, means formed in one of said compartments for taking up the vibration of the brush contained in said compartment, substantially as described.

7. Inabrush-holderhaving two superposed compartments extending parallel to each other, a spring-actuated plunger operating in one ot' said compartments and means for locking said plunger when not in use, substantially as described.

S. In a brush-holder having two superposcd compartments extending parallel to each other, the combination with the two walls forming the upper compartmentof two ledges, located at the upper edge of said walls for the purposes as set forth, substantially as described.

9. In a brush-holder having two superposed compartments extending parallel to each other, the combination with one .of the walls Aforming the upper compartment of a slot, a collector-spring for the purposes as set forth, and a projection formed on the outside of said wall for holding the collector-sprin g, substantially as described.

1U. In a brush-holder having two superposed compartments extending parallel to each other, the combination with the wall separating the two compartments of a longitudinal slot and a cut-out extending at right angles to the axis of the longitudinal slot and communicating with same at the point where the latter terminates, substantially as described.

Il. In a dynamo-electric machine the combination with a brush ha ving one side curved in cross-section ot' one of two superposed compartments of a brush holder, and means formed in said compartment for preventing the insertion of the brush wrong side up, substantially as described.

I2. In a dynamoeelectrie machine, a brush having one curved and three straight surfaces in cross-sectional outline, 'for the purposes as set forth, substantially as described.

I3. In an insulating brush-holder bracket and arm atu re-shield of a dynamo-electric machine, a Hat circular portion with two arms extended from said circular portion, a central shaft-hole, holes for the admission of screws and holes for the admission of the leadingout wires, substantially as described.

In testimony that I claim the foregoing I have hereunto set my hand this 19th day of July, 1899.

` CHARLES A. ECK.

lVitnesses:

AXEL V. BEEKEN, G. BnncnNnoI-tr. 

